The tiger is a breathtakingly charismatic species. It is the largest terrestrial carnivorous mammal on earth and sits on top of the food chain in tropical, grassland and boreal ecosystem s ranging from South Asia to Central Asia and Siberia in the former USSR. In these eco-regions, the tiger has served as a flagship mammal and hence acted as an umbrella species for overall biodiversity conservation management. It is an ecological indicator species from which wildlife biologists can detect various ecological changes in terms of species richness, size, equitability, biomass, etc. Some wildlife biologists refer to the tiger as an ecological litmus paper because of its role in helping to indicate the overall health of tropical ecosystem s in South and South-East Asia.